In the oil and gas industry, drill strings are used to drill into the earth and form wellbores. A drill string is made up of pipe sections (often referred to as pipes) connected end to end. At times, the entire drill string needs to be pulled out from a wellbore, e.g. for servicing and/or repair. Such operations may require a large number of connected pipe sections to be disconnected as the drill string is withdrawn from the wellbore and re-connected when the drill string is re-inserted into the wellbore. The disconnection and subsequent connection of these pipe sections can be time consuming, expensive and dangerous.
There is a general desire for an improved apparatus and method for handling a drill string. There is a general desire for an apparatus and method for withdrawing a drill string out from a wellbore and lowering the drill string back into the wellbore. There is a general desire to withdraw a drill string from a wellbore and to reinsert the drill string into the wellbore with minimal or no drill string disassembly, except possibly to repair a portion of the drill string.
The foregoing examples of the related art and limitations related thereto are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings.